Beyond Good and Evil: Part 2 - S4-E9
Audio problem: When Xavier says "Assemble the X-Men," his mouth movement is slightly out of sync. (00:05:55)
Beyond Good and Evil: Part 2 - S4-E9
Audio problem: When Magneto says "I see I must persuade you," his mouth is completely closed. (00:16:30)
Answer: Chris Potter, the original Gambit voice actor, did indeed quit the role in the 4th season. His last episode was The Phalanx Covenant Part 1 so it seems reasonable that Fox would limit the use of the character even though it was recast. It doesn't appear that Potter left the role due to animosity, he stated in an interview that he wished to play Gambit in the first live action X-Men film.
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